One aspect I loved about the Necromancer profession that carried over from Guild Wars 1, is the ability to apply conditions (debuffs) on enemies and spread them. It's like another way to deal damage aside from a direct damage route. This build is solely for that purpose, apply and stack conditions to multiple foes. You will be using Scepter/Dagger skills along with the Marks from the Staff set and Wells and Corruptions from your utility skills to get the job done...